水产品货架期预测模型的研究进展

水产品货架期预测的研究为监测和控制水产品安全提供了理论基础。水产品是一类极易腐败变质的产品,利用货架期预测可以对水产品贮藏、运输、销售等流通环节下的品质进行及时监控,从理论上预测水产品剩余货架期。本文分析了影响水产品货架期的主要因素,包括微生物作用、水产品化学反应、水产品物理变化以及环境温度的作用等;提出了2种水产品货架期的建模思路;并总结了几类常用水产品货架期预测模型(基于水产品品质损失的动力学模型、基于温度变化的模型、基于统计学的模型和人工神经网络模型等);最后分析了水产品货架期预测目前存在的问题,为未来研究提供思路。     

水产品贮运过程中货架期预测的研究进展

水产品具有富含水分、高度不饱和脂肪酸和高活性内源酶等原料学特性,加之其外源微生物和内源酶的联合作用,其在死后贮运过程中极易发生理化性质、微生物和感官性状的变化,引起品质下降。基于敏感指标的变化对水产品的货架期进行建模,对水产品品质的快速预测和评估具有十分重要的意义。本综述主要介绍了在贮运过程中水产品货架期预测的内涵、货架期预测模型的研究方法（等温法和加速实验法）、货架期预测模型的分类及国内外研究进展,旨在为水产品货架期预测建模提供参考。     

不同包装低盐腌制白萝卜贮藏货架期预测模型

我国腌制蔬菜业发展迅速,腌制蔬菜的加工与贮藏也备受关注,但关于腌制蔬菜贮藏过程中品质劣变规律及货架期预测等研究比较薄弱。通过不同包装方式的低盐腌制白萝卜成品在不同温度的贮藏条件下,探究感官品质评价、脆度、色差以及菌落总数随时间的变化规律,建立其品质变化的动力学模型,并预测了不同包装方式低盐腌制白萝卜成品的货架期,旨在为低盐腌制白萝卜产品的流通和贮藏提供技术参考。实验结果表明,随着贮藏温度的升高,透明包装组与铝箔包装组腌制白萝卜的感官评分、脆度逐渐降低,色差值、菌落总数逐渐增加,铝箔包装更有利于延缓品质劣变;对2种不同包装方式下温度(T)对腌制白萝卜脆度、色差值和菌落总数的变化速率(k)的影响,分别以1/T为横坐标,以lnk为纵坐标,进行线性拟合,其R~2均大于0.9,三者均有良好的线性关系;货架期预测中,透明包装方式下腌制白萝卜以菌落总数为特征指标建立的预测模型准确度较高,铝箔包装方式下腌制白萝卜以脆度为特征指标建立的预测模型准确度较高,温度越低,预测值越准确。     

水产品货架期模型的研究进展

本文对水产品的货架期模型研究进行了全面的综述,总结了水产品基于数学方程的预测模型和基于计算机人工神经网络模型的研究,包括:化学反应动力学模型、基于温度变化的货架期模型、微生物生长非生长预测模型以及人工神经网络模型在水产品中的应用。通过比较分析各种预测模型的优势,为水产品的品质保鲜与安全保障技术提供支持。     

水产品新鲜度综合评价与货架期预测模型的构建研究进展

对近年来水产品新鲜度的评价方法进行了分析,包括传统的评价方法和国内外最新的方法;同时介绍了水产品的货架期预测模型,包括一级、二级和三级模型;最后提出了水产品新鲜度综合评价和货架期模型构建的主要问题和研究方向,以期为今后水产品的品质和相关保鲜技术的研发提供一定参考。     

《腌制生食动物性水产品卫生标准》应用与建议

目的通过讨论GB10136—2005《腌制生食动物性水产品卫生标准》的实际应用情况与存在不足,为修订腌制生食动物性水产品卫生标准和卫生监管提供依据。方法采取现场调查、评价比较、综合分析等方式,对GB10136—2005设定的指标限值与应用进行分析。结果在现有工艺条件下,瓶装醉泥螺产品的菌落总数基本符合标准要求,但蟹糊合格率低,标准中列出了铅、镉的测定方法内容,但未作限量要求。结论新标准的实施,使得各种腌制生食动物性水产品有了统一明确的评判依据,建议对不同类别的腌制生食动物性水产品微生物指标进行分值限定,同时参照有关国际标准增设重金属指标铅、镉的限量要求,且不宜将指标值限得过低。     

两种低钠咸味剂腌制大黄鱼片的贮藏品质比较

为探明两种低钠咸味剂腌制处理对大黄鱼片贮藏品质的影响,本文以本实验室开发的低钠咸味剂A（氯化钠3.52%、氯化钾3.09%、葡萄糖酸钠0.60%）和低钠咸味剂B（氯化钠3.52%、氯化钾3.09%、葡萄糖酸钠0.60%、YE 0.30%、壳聚糖1.48%）分别腌制大黄鱼片,采用真空包装、气调包装和普通包装对腌制大黄鱼产品进行包装,分析其在4与?3 ℃贮藏期间的品质变化,并以7.50%的食盐腌制作为对照组。结果表明,无论采用哪种包装方式和贮藏条件,低钠咸味剂B腌制的大黄鱼片品质均优于低钠咸味剂A和对照组。产品在?3 ℃贮藏的品质变化速率均低于4 ℃贮藏的。低钠咸味剂B腌制大黄鱼片,采用气调包装在4 ℃贮藏的货架期是12 d,比真空包装延长1 d,也比低钠咸味剂A组延长货架期4 d;在?3 ℃贮藏的货架期是38 d,比真空包装延长20 d,比低钠咸味剂A组延长货架期10 d;且产品在外观、气味及色泽的感官评分均优于低钠咸味剂A组和对照组。本研究为减盐减钠的鱼类腌制加工提供技术支撑,也为其在产业应用提供技术参考。     

辐照水产品的热释光检测方法研究

研究热释光分析方法应用于辐照水产品检测的可行性。首先分离出水产品中的硅酸盐类矿物质,然后在加热条件下测量这类矿物质中由辐照而积蓄的并以光子释放的能量,从而判断食品是否经过辐照。试验以牡蛎、虾皮、贻贝和腌制泥螺为例进行了研究。结果表明,应用热释光分析方法检测辐照水产品具有较高的可靠性。     

预测微生物学在水产品货架期中应用研究进展

预测微生物学可通过数学建模来快速预测水产品中腐败菌和致病菌的生长规律,从而预测水产品的货架期。文章阐述了预测微生物学初级模型、二级模型、三级模型的含义,列举了预测微生物学在水产品货架期中的应用,分析了预测微生物学在水产品货架期预测中存在的问题,并对预测微生物学的应用前景进行展望。     

复合无硝腌制剂在乳化香肠中的应用效果研究

研究一种由多种添加剂复合而成的无硝腌制剂对乳化香肠的腌制效果。与使用亚硝酸钠的传统腌制方法相比,添加此复合无硝腌制剂腌制后的乳化香肠在色度、抗氧化性、质构和感官品质方面均无显著性差异（P〉0．05）,而在贮藏期间其菌落总数和亚硝酸钠残留量显著（P〈0．05）降低,说明其能够延长乳化香肠的货架期,提高食用安全性。结果表明,此种复合无硝腌制剂取代亚硝酸钠应用于乳化香肠的腌制过程是可行的。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press